Sighting apparatus for ordnance.



'No. 826,836. PATENTED JULY 24, 1906. A. T. DAWSON & 9,1". BUGKHAM. SIGHTING APPARATUS FOR onnmnon.

Amman-101w rum) DBO- a. 1905.

a sums-sum 1.

'Qea veZlBucZ/anv THE NORRIS PETERS ca., wasrmvaron, n c.

No. 826,836, PATENTED JULY 24, 1906.

I A. T.; DAWSON a. G. T. BUGKHAM. SIGHTING APPARATUS POR'OR'DNANGB.

APPLICATION FILED DEG. B. 1905 3 SHEETfi-SHEET 2.

172w Z076 51% a? 1127a wdan m' wdd 1n: NORRIS PErERs cc., wAsHmamN n c PATBNTED' JULY 24, 1906. A. T. DAWSON & G. T. BUGKHAM.

SIGHTING APPARATUS FOR ORDNAN GE. APPLIOATIOH FILED DBO. s, 1905.

3 SHEETS-SHEET 3.

ma lvoRms PETERS ca, Wasnmanm, o. c.

UNITED STATES PATENT oEEicE,

ARTHUR TREVOR DAWSON AND GEORGE THOMAS BUOKHAM, OF WEST MINSTER, LONDON, ENGLAND, ASSIGNORS TO VIOKERS SONS & MAXIM,,

SIGHTING APPARATUS FOR ORDNANCE.

NO. 826,836. Patented July 24,119 064 Original application filed September 29, 1904, Serial'No. 226,587. Divided and this application filed December 8 1905- eriali Specification of Letters Patent.

A is the usual bracket, which is aflixed to the gun-mounting and to which the radial sight-bar A is hinged at a, said sight-bar aving the usual laterall -displaceable pivoted h 1 carrier at for the telescopic or To all whom it may concern:

Be it known that we, ARTHUR TREVOR DAWSON, lieutenant of the Royal Navy, director and superintendent of Ordnance Works, and GEORGE THOMAS BUOKHAM, engineer, subjects of the King of Great Britain, residing at 32 Victoria street, Westminster, in the county of London, England, have invented certain new and useful Improvements Relating to Sighting Apparatus for Ordnance, of which the following is a specifio der or other sight.

113 is the range-dial, and O the deflectiondia 6o B is the sight-setting hand-wheel forelevating the sight-bar A through the intervention of the gearing hereinafter described, said hand-wheel being situated at the side of the sighting apparatus to permit of the latter being actuated by a separate sight-setter. b is the axle, carrying the worm-wheel b and elevating-pinion I2 and b is another axle carrying the range-dial B and situated eccentrically with respect to the axle b.

b is the groove or slot in the range-dial for the reception of a crank-pin on the crank 6 the said crank-pin bein preferably furnished with a block 6 for s iding in the said slot. The crank b is mounted on the axle b, which receives rotary motion from a worm b gearing with the worm-wheel b. The said worm is mounted on a spindle b, which is geared by bevel-pinions b with the sightsetting hand-wheel B By actuating said hand-wheel B the axle b and its crank b are angularly displaced, whereby the crank-pin is caused to slide in the groove or slot 6 and impart angular movement to the range-dial. As the an ular displacement of the sight-bar A about t e hinge (1 increases the path ofthe crank-pin extends farther from the axis of the range-dial, owing to the eccentric position of the crank-axle b relatively to said axis, so thatthe pin 6 moves outward along 0' e groove or-slot b and thereby imparts a gradually-increasing angular displacement to the range-dial, with the result that we obtain a uniform or approximately uniform movement of the dial during the sight-set ting operation and a consequent equality or approximate equality of the graduations on the range-dial. The range-dial revolves in a stationary ring B, having a pointer B at we claim, and desire to secure by LettersPatent of the United States, is-

1. In gun-sighting apparatus, the combination with the sight-setting mechanism, of a range-dial having a groove therein, a crank cation.

This invention relates to sighting apparatus for ordnance.

As is well known, the graduations on a range-dial are ordinarily very close together at short ranges and more widely spaced at long ranges, thus rendering the sight-setting operation difficult to perform at short ranges, owing to the closeness of the graduations and the consequent difficulty in reading them cor ly. This is a disadvantage which it is chief object of our invention to so that the graduations on the range-dial will be equal or approximately equal throughout. For this purpose the axle carrying the toothed pinion that engages with the sightelevating rack has a worm -wheel with which a worm engages for actuating said axle. On this axle is mounted a crank which engages with a groove or slot in the range-dial, said crank and slot being so disposed relatively to each other that the angular movement imparted to the range-dial by the sight-setting mechanism is regular or uniform, or approximately regular or uniform, notwithstandin the variable nature of the movement that has to be imparted to the elevating-pinion in changin the range.

In or er that our said invention may be clearly understood and readily carried into effect, we will describe the same more fully with reference to the accompanying drawings, in which Figure l is a side elevation of sighting apparatus provided with our improved sightsetting and range indicating mechanism. Figs. 2 and 3 are respectively a side elevation and a vertical central section, on a larger scale, showing the range-dial and the mechanism directly connected therewith for actuating the same.

. tuating said eccentric crank-axle simultaneof the range-dial, a toothed pinion on said eccentric crank-axle engaging with the sightelevating rack, and means for actuating said eccentric crank-axle engaging with said groove, an axle carrying said crank and eccentrically situated with respect to the axis of rotation of the range-dial, means for operating the sight-setting mec anism and means for actuating said eccentric crank-axle simultaneously with the operation of said sight-setting mechanism for the purpose specified.

2. In gun-sighting apparatus, the combination with the sight-setting mechanism, of a range-dial having a more or less radial groove therein, a crank engaging with said groove, an axle carrying said crank and eccentrically situated with respect to the axis of rotation of the range-dial, means for operating the sight-setting mechanism, and means for acsubstantially as and for the purpose specified.

4. In gun-sighting apparatus, the combination with the sight-setting mechanism, of a range-dial having a more or less radial groove therein, a crank engaging with said groove, an axle carrying said crank and eccentrically situated with respect to the axis of rotation of the range-dial, a toothed pinion on said eccentric crank-axle engaging with the sightelevating rack, a worm-wheel on said eccentric crank-axle engagin with, a worm, an means for actuating sai worm substantially as and for the purpose specified.

In testimony whereof we have hereunto set our hands, in presence of two subscribing witnesses, this 23d day of November, 1905.

ARTHUR TREVOR DAWSON.

GEORGE THOMAS BUCKHAM.

Witnesses:

HENRY KING,

ALFRED PEAKS.

ously with the operation of said sight-setting mechanism for the purpose specified.

, 3. In gun-sighting apparatus, the combination with the sight setting mechanism, of a range-dial having a more or less radial groove therein, a crank engaging with said groove, an axle carrying said crank and eccentrically situated with respect to the axis of rotation 

